This invention relates to structure for facilitating the process of dialysis in artificial kidney systems and the like.
In artificial kidney systems, blood is withdrawn from a patient and applied to a dialyzer through which dialysate solution is circulated and then, by the process of dialysis, chemical wastes, electrolytes and water in the blood pass into the dialysate solution (and in some cases vice versa) through thin walls of a membrane structure, such as hollow fibers, carrying the blood. The dialysate solution containing the wastes and water is drawn from the dialyzer and disposed and the blood is returned to the patient. This process of transporting wastes and water from the blood is referred to as hemodialysis.
Currently used dialyzers of dialyzer cartridges typically include a bundle of hollow fibers potted at either end in rubber or other suitable material for holding the fibers. The cross section of the bundle and the potting material is circular to enable insertion of the bundle into a cylindrically-shaped container. Blood is then introduced into one end of the container to flow through the fibers to the other end and dialysate solution is introduced near the central portion of the container to flow about the exterior surfaces of the fibers and then out again. With this configuration, the cross-sectional area of the potting material is rather large and, since the material is supported only around its periphery, pressures caused by the dialysate solution and the blood may cuase the material to deform, fracture and leak. This configuration may also present fabrication problems, from a quality control standpoint, because of the large cross-sectional area of the potting material and the difficulty of depositing potting material around the ends of the fibers. Finally, the cylindrically-shaped dialyzer cartridge container can accommodate only one fiber bundle size thus necessitating a change in both the container and the fiber bundle when a dialyzer cartridge having a different dialyzing effective area is desired.